Reishi mushroom

What is it?

Reishi mushroom is a fungus that some people describe as “tough” and “woody” with a bitter taste. The fruiting body (above-ground part) and mycelium (filaments connecting a group of mushrooms) are used as medicine.

Reishi mushroom is used for boosting the immune system; viral infections such as the flu (influenza), swine flu, and avian flu; lung conditions including asthma and bronchitis; heart disease and contributing conditions such as high blood pressure and high cholesterol; kidney disease; cancer; and liver disease. It is also used for HIV/AIDS, altitude sickness, chronic fatigue syndrome (CFS), trouble sleeping (insomnia), stomach ulcers, poisoning, and herpes pain. Other uses include reducing stress and preventing fatigue.

In combination with other herbs, reishi mushroom is used to treat prostate cancer.

Insufficient Evidence to Rate Effectiveness for...

Noncancerous tumors in the colon and rectum (colorectal adenomas). Early research suggests that taking reishi mushroom extract daily for 12 months reduces the number of tumors in people with colorectal adenomas.

Clogged arteries. Early research suggests that taking a specific reishi mushroom product (Ganopoly) reduces symptoms of clogged arteries, including chest pain and shortness of breath.

Diabetes. Early research suggests that taking a specific reishi mushroom product (Ganopoly) daily for 12 weeks reduces hemoglobin but not blood sugar levels in people with type 2 diabetes.

Hepatitis B. Early research suggests that taking a specific reishi mushroom product (Ganopoly) for 12 weeks reduces how much of the hepatitis B virus is circulating in the body. This product also seems to improve liver function in people with this condition.

High cholesterol. Early research suggests that taking reishi mushroom extract daily for 12 weeks does not affect cholesterol levels in people with high blood pressure and/or high cholesterol.

High blood pressure. There is inconsistent evidence about the effects of reishi mushroom on high blood pressure. Early research suggests that taking reishi mushroom extract daily for 12 weeks does not lower blood pressure in people with slightly high blood pressure. However, other research suggests that taking reishi mushroom lowers blood pressure in people with more severe high blood pressure.

Lung cancer. Early research suggests that taking reishi mushroom does not shrink lung tumors. However, it does appear to improve immune function and quality of life in people with lung cancer.

Shingles-related pain. Some people report that hot water extracts of reishi mushroom decreases pain when conventional treatment does not work.

Boosting the immune system.

Viral infections.

Prostate cancer.

Asthma and bronchitis.

Stress.

Kidney disorders.

Liver disease.

HIV disease.

Altitude sickness.

Fatigue.

Chronic fatigue syndrome (CFS).

Trouble sleeping (insomnia).

Stomach ulcers.

Poisoning.

Other conditions.

More evidence is needed to rate the effectiveness of reishi mushroom for these uses.

Reishi mushroom extract is POSSIBLY SAFE when taken by mouth appropriately for up to one year.

Reishi mushroom is POSSIBLY UNSAFE when taken by mouth in a powdered form for more than one month. Use of powdered reishi mushroom has been associated with toxic effects on the liver.

Reishi mushroom can also cause other side effects including dryness of the mouth, throat, and nasal area along with itchiness, stomach upset, nosebleed, and bloody stools. Drinking reishi wine can cause a rash. Breathing in reishi spores can trigger allergies.

Special Precautions & Warnings:

Pregnancy and breast-feeding: There is not enough reliable information about the safety of taking reishi mushroom if you are pregnant or breast feeding. Stay on the safe side and avoid use.

Bleeding disorder: High doses of reishi mushroom might increase the risk of bleeding in some people with certain bleeding disorders.

Low blood pressure: Reishi mushroom seems to be able to lower blood pressure. There is a concern that it might make low blood pressure worse and could interfere with treatment. If your blood pressure is too low, it is best to avoid reishi mushroom.

A clotting disorder called thrombocytopenia: High doses of reishi mushroom might increase the risk of bleeding in people with thrombocytopenia. If you have this condition, do not use reishi mushroom.

Surgery: High doses of reishi mushroom might increase the risk of bleeding in some people if used before or during surgery. Stop using reishi mushroom at least 2 weeks before a scheduled surgery.

Herbs and supplements that might lower blood pressure

Reishi mushroom might lower blood pressure. Taking it along with other herbs and supplements that have this same effect might make blood pressure drop too low. Some of these herbs and supplements include andrographis, casein peptides, cat's claw, coenzyme Q-10, fish oil, L-arginine, lycium, stinging nettle, theanine, and others.

Herbs and supplements that might lower blood sugar

Reishi mushroom might lower blood sugar. Using it along with other herbs and supplements that have the same effect might cause blood sugar to drop too low in some people. Some of these products include alpha-lipoic acid, bitter melon, chromium, devil's claw, fenugreek, garlic, guar gum, horse chestnut seed, Panax ginseng, psyllium, Siberian ginseng, and others.

Herbs and supplements that might slow blood clotting

The effect of reishi mushroom on blood clotting is not clear. Higher amounts (about 3 grams per day) but not lower doses (1.5 grams per day) might slow blood clotting. There is a concern that taking reishi mushroom along with other herbs that slow blood clotting could increase the risk of bruising and bleeding. Some of these herbs include angelica, anise, arnica, clove, danshen, garlic, ginger, ginkgo, Panax ginseng, horse chestnut, red clover, turmeric, and others.

The appropriate dose of reishi mushroom depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for reishi mushroom. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

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